P1456: MULTIPARAMETRIC CMR AND CARDIAC COMPLICATIONS IN THALASSEMIA INTERMEDIA
Authors: Antonella Meloni, Laura Pistoia, Amalia Acquafredda, Piera Giovangrossi, Letizia Tedesco, Angelica Barone, Sabrina Bagnato, Stefania Renne, Priscilla Fina, Giuseppe Peritore, Vincenzo Positano, Filippo Cademartiri
Journal: HemaSphere (2023)

Topic: 27. Thalassemias Background: The key role of multiparametric Cardiac Magnetic Resonance (CMR) for the cardiac risk stratification of thalassemia major patients has been clearly demonstrated. Aims: We explored the association between multiparametric CMR findings (iron, function, and replacement fibrosis) and cardiac complications in a relatively large cohort of thalassemia intermedia (TI) patients. Methods: We considered 254 beta-TI patients (43.14±13.69 years, 138 females) consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia project. Iron overload was quantified by T2* technique and biventricular function and atrial areas by cine images. Macroscopic myocardial fibrosis was detected by late gadolinium enhancement technique. Results: Twenty-five (9.8%) patients had an history of cardiac complications: 4 heart failure, 17 supraventricular arrhythmias, 3 ventricular arrhythmias, and one hypokinetic arrythmia. No difference between patients without and with a positive history of cardiac complications was detected in terms of gender, presence of regular transfusions, mean serum ferritin levels, MR liver iron concentration (LIC) values, global heart T2* values, biventricular volumes and left ventricular mass indexed by body surface area, and biventricular ejection fractions. Compared to patients free of cardiac complications, patients with a positive history of cardiac complications were significantly older (55.42±10.37 vs. 41.80±13.35 years; p<0.0001) and showed a significantly increased left atrial area index (15.62±3.83 vs. 13.18±2.46 cm2/m2; p=0.005) and a significantly higher frequency of replacement myocardial fibrosis (54.5 vs. 22.8 %; p=0.034). When age>75th percentile (corresponding to 51.35 years), left atrial area index>75th percentile (corresponding to 15.13 cm2/m2), and replacement myocardial fibrosis were included as covariates in the logistic regression analysis, increased age and replacement myocardial fibrosis remained significant risk markers for cardiac complications (Table 1). Table 1. Logistic regression analysis assessing the risk factors associated with a positive history of cardiac complications. - Univariate Multivariate OR (95% CI) p-value OR (95% CI) p-value Age>75th percentile 10.23 (4.03-25.95) <0.0001 4.26 (1.13-16.05) 0.041 Left atrial area index>75th percentile 3.07 (1.15-8.17) 0.025 Replacement myocardial fibrosis 4.06 (1.13-14.63) 0.032 3.99 (1.06-15.06) 0.041 OR, odds ratio; CI, confidence intervals. Summary/Conclusion: Replacement myocardial fibrosis emerged as the CMR marker more strongly associated with a positive history of cardiac complications. The lack of an association between MIO and cardiac complications can be explained by the low levels of cardiac iron and by the fact that the most frequent complication was represented by supraventricular arrythmias. It has been shown that MIO contributes less to the development of arrhythmias than cardiac failure. Our findings suggest that multiparametric CMR can be used as a guide to improve cardiac management also in TI. Keywords: Magnetic resonance imaging, Thalassemia, Complications